Obstructive Lung Disease Flashcards
1
Q
driving pressure
A
=Pplat-PEEP and represents the ratio between TV and compliance
2
Q
obstructive lung diseases characteristic
A
largely normal TLC
decreased FEV ratios
characterized by airflow limitation
3
Q
OSA definition
A
mechanical obstruction of breathing that occurs during sleep when pharyngeal muscles relax
4
Q
OSA precipitating factors
A
obesity is biggest one, and usually males
5
Q
OSA clinical features
A
hypoxemia, hypercarbia, low FRC, comorbidities related to obesity and hypoxemia
hallmark: snoring, fragmented sleep, daytime somnolence
6
Q
OSA comorbidities precipitated by obesity and hypoxemia
A
systemic and pulmonary hypertension
ischemic heart disease
CHF
7
Q
OSA dx
A
polysomnography, berlin test, STOPBANG
8
Q
polysomnography
A
records number of abnormal respiratory events.
includes apnea plus hypo apnea index, AHI
9
Q
AHI score
A
> 5 associated with sleep related symptoms
15 is diagnosis for moderate OSA
30 severe OSA
10
Q
STOPBANG pneumonic
A
Snores loudly daytime tiredness observed stop breathing high pressure BMI >35kg/m^2 age >50y neck circumference >40cm gender: male
11
Q
what does an obstructive flow volume curve look like
A
normal inspiration, scooping during exhalation. indicative of asthma, COPD, air trapping
12
Q
what does a flow volume curve look like for a fixed obstruction
A
even and smaller inhalation and exhalation curves. can’t breathe in deep, can’t breathe out fast. example is tracheal stenosis
13
Q
what does a flow volume curve look like for an extra thoracic lesion
A
exhalation largely normal, inhalation almost nonexistent. lesion outside chest wall is making it hard to breathe. when you exhale, you “blow out the narrowing”
14
Q
what does a flow volume curve look like for an intra thoracic lesion
A
inspiration largely normal, exhalation largely abnormal/lessened.
15
Q
what does spirometry include (6)
A
FEV1, FVC, FEV1/FVC ratio, FEV25-75%, MVV, DLCO
16
Q
FEV1
A
forced expiratory volume measured in 1 second. the volume of air forcefully exhaled in once second (normal is 80-120% of TLC. 80% would be ~4L)
17
Q
FVC
A
forced vital capacity. the volume of air forcefully exhaled after a deep inhalation. (3.7L in females, 4.8L in males)
18
Q
FEV1/FVC ratio
A
normal is 75-80%. amount you can blow out in 1 second versus how much you blow out completely.
19
Q
FEV 25-75%
A
measurement of air flow at midpoint of a forced exhalation. tells you about exhalation sustainability
20
Q
maximum voluntary ventilation (MVV)
A
maximum amount of air that can be inhaled and exhaled in one minute (or 15s).
males are usually 140-180
females usually 80-120L/min
21
Q
DLCO
A
diffusing capacity. volume of carbon monoxide (CO) and helium transferred across the alveoli into the blood per minute per unit of alveolar partial pressure. a single breath of .3% CO and 10% helium is held for 20 seconds. normal value is 17-25mL/min/mmHg
22
Q
s/sx of URI, general
A
non productive cough, sneezing, rinorrhea
23
Q
s/sx of URI, bacterial
A
more serious. includes fever, purulent nasal discharge, productive cough, malaise. patients may present tachypneic and wheezy. active fever, may cancel.
24
Q
risk factors for pediatric patient complications include
A
actively sick
history of reactive airway disease
ETT intubation
airway surgery
25
if you cancel a surgery r/t a URI, how long will it be postponed?
at least 6 weeks
26
anesthetic management of URI patients include
hydration
reduction of secretions
limiting airway manipulation (induce when completely relaxed/deep)
LMA v ETT. while LMA is "no airway manipulation", you have higher aspiration risk
27
adverse respiratory events related to URI patients include
bronchospasm (run them deep), laryngospasm (CPAP usually breaks it), airway obstruction, postoperative croup (usually self limiting), desaturation
28
asthma definition and characteristics
reversible airway obstruction. episodic.
(inflammation, edema, airway narrowing, decreased ability to exhale)
characterized by bronchial hyperreactivity, bronchoconstriction, chronic inflammation of lower airways
29
asthma pathophysiology
activation of inflammatory pathway leads to infiltration of airway mucous with eosinophils, neutrophils, mast cells, T cells, B cells. inflammatory mediators include histamine, prostaglandin D, leukotrienes.
airway edema results, thickening of basement membrane. simultaneous edema and repair
higher risk for anesthesia complications
30
how long does asthma episode last
minutes to hours
31
asthma clinical manifestations
wheezing, productive and nonproductive cough, dyspnea/SOB, chest discomfort leading to air hunger, eosinophilia
32
status asthmaticus
episode of asthma/"bronchospasm" that persists despite tx
33
asthma and dx
usually based on s/sx
-obstruction is partially reversible with bronchodilators
PFT's including FEV1 <35% normal
downward scooping of expiratory limb of flow volume curve
increase in FRC but TLC remains WNL
DLCO unchanged, not a diffusion issue
34
do ABG's tell you much about an asthma exacerbation
based on level of disease
normal ABG in mild disease
hypocarbia and respiratory alkalosis can be commonly seen, reflects neural reflex changes in lungs, not hypoxemia
severe obstruction r/t PaO2 <60mmHg, rises in PaCO2 noted when FEV1 less than 25%. fatigue in accessory muscles contributes to hypercarbia
35
what does a severe* asthmatic look like on CXR
hyperinflation, hilar congestion due to mucous plugging and pulmonary hypertension
36
what may an EKG look like on an asthma patient
RV strain associated with increased pulmonary pressures may be evident. this would be T wave inversion in R precordial leads (V1-4) and inferior leads (II, III, aVF)
37
treatment of asthma
```
emphasis of treatment is on inflammation and bronchospasm.
includes corticosteroids
long acting bronchodilators
leukotriene modifiers
anti IgE monoclonal antibody
methylxanthines
mast cell stabilizer
```
38
corticosteroid used with asthma patient treatment
beclamethasone
39
long acting bronchodilators used with asthma patient treatment
salmeterol or
| combo of symbicort and advair
40
leukotriene modifier used with asthma patient treatment
singulair
41
anti IgE monoclonal antibody used with asthma patient treatment
omalizumab
42
methylxanthines used with asthma patient treatment
theophylline (PDE inhibitor, can be toxic)
43
mast cell stabilizer used with asthma patient treatment
cromolyn
44
what FEV1 % indicates that an asthmatic would be symptom free
>50%
45
status asthmaticus pharmacological treatment
B2 agonists including metered dose inhaler, nebulizer (usually given in preop), injection of terbutaline.
IV corticosteroids
1g mag sulfate to relax muscles
oral leukotriene inhibitor
46
status asthmaticus non pharmacological treatment
supplemental O2 if SpO2<90%
| -if resistant to ex's, think airway edema and secretions.
47
why dont you give an asthmatic anticholingerics
they need to stay hydrated
48
why dont you give an asthmatic anticholinergics
they need to stay hydrated
49
what questions should you ask an asthmatic/what information would you want preoperatively on an asthmatic
disease severity and tx effectiveness are big ideas
severity and characteristics of asthma, including use of accessory muscles and active wheezing
previous ICU admissions/intubations
how many ICU admissions/intubations in past year
eosinophil counts (inflammatory process) (CBC, WBC's)
PFT results at baseline and after bronchodilator therapy to assess responsiveness
presence of co existing diseases
50
for asthmatics, what FVC or FEV1/FVC % is associated with perioperative risk?
FVC >70%
| FEV1/FVC <65%
51
anesthetic considerations for asthmatics related to induction
try to avoid a general, but if you have to put them asleep maybe try an LMA
continue all meds until time of surgery and give stress dose steroids
try deep induction
IV or transtracheal lidocaine induction (and on emergence)
sufficient volatile agent to suppress reactivity of airways
avoid histamine releasing drugs including narcotics (morphine) and paralytics (succ)
52
if an asthmatic starts to have a bronchospasm intraoperatively during a general, do you turn up the gas
no, it won't get to the alveoli. try to get them deep with prop.
administer B2 agonist, consider steroids or mag, administer NMB
53
anesthetic considerations for asthmatics perioperatively
light anesthesia can facilitate a bronchospasm
IE ratio adjustment to prevent air trapping (careful with this)
adequate fluid administration
avoid anticholinergic drugs
54
anesthetic considerations for asthmatics and emergence
deep extubation as long as you know theyre sufficiently breathing on their own
55
COPD definition
non reversible loss of alveolar tissue and progressive airway obstruction. third leading cause of death by 2030
56
risk factors for COPD
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cigarette smoking!!!!!!
occupational exposures
pollution
recurrent respiratory infections
low birth weight
a1 antitrypsin deficiency
```
57
two types of COPD
bronchitis, or type B patients. "blue bloaters"
| emphysema, or type A patients. "pink puffers"
58
characteristics of emphysema
characterized by enlargement of air spaces distal to the terminal bronchiole with destruction of walls.
loss of alveoli and damage to capillaries
small airways are thin, tortuous and atrophied
obstruction of matrix in lower alveolar sacs= shunting and dead space
59
centriacinar emphysema
are usually more proximally located on actual alveoli, more common in apex of lung
60
panacinar emphysema
either no regional preference, or seen more distally in lobes. depends on who you talk to
located more distally on alveoli
-seen in lower lobes d/t a1 antitrypsin deficiency
61
paraseptal emphysema
specific regions of lungs
62
bullae
1 big sac versus large alveolar sacs (blown all the way out)
63
acinus
describes tissue distal to terminal bronchioles
64
neutrophils and emphysema
neutrophils block lysosomal elastane release
65
a1 antitrypsin deficiency and emphysema
elastane proliferates, allows for breakdown. congenital in nature.
66
chronic bronchitis characterized by
excessive sputum production/expectoration of sputum most days for at least 3 months for 2 successive years
67
hallmark findings of chronic bronchitis
hypertrophy of mucus glands of large bronchi
inflammatory changes in small airways that leads to edema
granulation of tissue, smooth muscle increases. increased thickness, decreased airflow
peri bronchial fibrosis
usually patients are in 50's and older
68
emphysema, PaO2, hypoxemia, diaphragm
PaO2 70's-80's, not as hypoxemic, inflated lungs flattens diaphragm. all related to distraction of matrix
69
chronic bronchitis, PaO2, hypoxemia, changes related to pulmonary vasculature
PaO2 60's or lower, chronically hypoxemia, pulmonary vasculature changes, pHTN, HF, and edema can ensue
70
definitive dx of COPD requires
spirometry
71
```
COPD PFT results:
FEV1/FVC ratio:
FEV25-75:
FRC;
TLC:
RV:
```
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FEV1/FVC ratio: decreased. <70% means not reversible with bronchodilators
FEV25-75 decreased
FRC increased
TLC increased
RV increased
```
72
GOLD spirometric criteria
determines severity of COPD, global initiative for chronic obstructive lung disease. a bunch of world health organizations getting together and making up pneumonics to feel like theyre contributing to a cause, whats new.
73
COPD tx
designed to relieve sx and slow disease progression
smoking cessation
long term O2 administration, usually 2lpm NC
drug tx (long acting B2 agonists, inhaled corticosteroids, long acting anticholinergic drugs)
vaccinations
diuretics
systemic corticosteroids
theophylline
exercise training programs
74
long term O2 administration usually suggested when:
PaO2 <55mmHg
Hct >55%
evidence of for pulmonale
75
drug treatment of COPD includes
long acting B2 agonists
inhaled corticosteroids
long acting anticholinergic drugs
76
Lung volume reduction surgery and mechanisms of improvement
indicated for severe cases of COPD, take out bad lobe to optimize rest of lung. idea is decreased shunting, decreased dead space, increase in elastic recoil, decrease in amount of hyperinflation, improved diaphragmatic and chest wall movement
77
lung volume reduction surgery anesthetic considerations
double lumen tube, avoidance of N2O, avoidance of excessive positive pressure ventilation, LPV, 1 lung ventilation means 3-4ml/kg TV.
78
COPD anesthetic considerations preoperatively
preop hx important
smoking history including pk/yr, when they quit
know current meds/continue through DOS
oxygen use/CPAP machine
exercise tolerance/METS score
frequency of exacerbations "how often does this disease debilitate you"
most recent exacerbation and its course
use of non invasive PPV
clinical signs more predictive of pulmonary complications ex)dyspneic, use of accessory muscles, wheezing
79
COPD anesthetic considerations: should they get PFT's?
yes if:
hypoxemia or need for home O2 with no known cause
NaHCO2 >33mEq/L
PaCO2 >50mmHg
hx respiratory failure d/t persistent problem
severe SOB r/t disease
planned pneumonectomy
difficulty assessing pulmonary status through clinical means
differential diagnosis needed
need to determine response to bronchodilators
pHTN
80
COPD anesthetic considerations: postoperative complications risk
active clinical s/sx: wheezing, SpO2 <90, no meds taken, has comorbities, METS<3, elderly
age >60
ASA III or IV
current smoker, >60pk/year hx
cardiovascular involvement (RV fx should be assessed by cardiology)
low albumin <3.5g/dL
type of surgery
81
COPD risk reduction strategies
cease smoking for at least 6weeks, 8 weeks optimal
optimize nutritional status because malnutrition increases risk of pleural leaks after lung surgery
regional anesthesia because peripheral nerve blockade carries little risk for pulmonary complications
82
what can happen with inter scalene block
ipsilateral phrenic nerve palsy, paralyze diaphragm for duration of block.
83
COPD during general anesthesia: volatile agent, N2O, benzodiazepine/opioid considerations
volatiles are useful because theyre rapidly eliminated and especially sevoflurane has bronchodilators effects
avoid N2O with any lung pathology where expansion would be detrimental. attenuates HPV, causes VQ mismatch
careful with benzos and opioids, normal dosages can have increased effect on them
84
COPD and mechanical ventilation
humidification
avoid hemodynamic hyperinflation of the lungs
Vt 6-8mL/kg
PIP <30cmH2O
FiO2 titrated to maintain SpO2 >90%
so LPV.
(if Pip greater than 30, driving pressure likely >20. not chill)
85
COPD and air trapping and cascade of events
aka auto peep, PPV applied without sufficient expiration. increases intrathoracic pressure, decreases venous return, increases pulmonary arterial pressure, results in right heart strain
86
COPD and bronchospasm: what to do
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deepen anesthetic
deliver short acting bronchodilator
suction secretions
IV steroids
epi if needed
```
87
COPD postoperative considerations to optimize this patient
lung expansion maneuvers including IS and deep breathing
early ambulation
neuraxial anesthesia
88
expiratory outflow obstructions (5)
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bronchiectasis
cystic fibrosis
primary ciliary dyskinesia
bronchiolitis obliterans
tracheal stenosis
```
89
bronchiectasis definition, result
irreversible airway dilation and collapse resulting from inflammation due to chronic infections. pseudomonas is most common organism cultured
resultant airway collapse increases susceptibility for recurrent infections. once established, nearly impossible to eradicate
90
bronchiectasis distinguishing factors (from bronchitis)
nasty purulent sputum, hemoptysis (200mL over 24 hour period means significant), pleuritic pain, finger flubbing
91
bronchiectasis dx
hx of chronic cough with purulent sputum
92
bronchiectasis dx imaging
CT to confirm disease presence and location
93
bronchiectasis s/sx
hemoptysis, dyspnea, wheezing, pleuritic chest pain, finger clubbing
94
bronchiectasis anesthetic considerations: preoperative
get a detailed patient history including severity, most recent exacerbations, meds taken, make sure to continue DOS
elective procedures should be delayed until patient optimized unless surgery is to correct this
95
bronchiectasis and GETA
frequent suctioning, double lumen tube to prevent R to left contamination since this disease is usually pocketed versus diffuse
avoid nasal intubations
96
cystic fibrosis (CF) definition of disease
autosomal recessive disorder affect a single gene on chromosome 7. prevents chloride transport and movement of salt and water in and out of cells. also episodic.
(r/t CFTR or cystic fibrosis transmembrane conductance regulator)
-results in abnormally thick sputum production outside of epithelial cells
-this is all cells, not just lung cells. usually anything with secretory ducts.
97
CF provokes damage to
```
lungs (bronchiectasis, COPD)
sinusitis
pancreas (DM)
liver (cirrhosis)
Gi tract (ileus)
reproductive organs (azoospermia)
```
98
CF primary cause of morbidity and mortality
chronic pulmonary infection
99
CF dx
sweat chloride concentration >70mEq/L
| -presence of normal sinuses is strong evidence that CF is NOT present
100
CF clinical manifestations
chronic purulent sputum production
malabsorption with response to pancreatic enzyme therapy
bronchoalveolar lavage high in neutrophils
COPD common in most adult patients
101
CF tx
directed towards allegation of symptoms: airway secretion clearance, correction of organ dysfunction, nutrition, prevention of intestinal obstruction
gene therapy currently being investigated to replace chromosome 7, so this pt needs to be optimized. CPT!
may be taking VitK to help absorb fat soluble vitamins
102
CF anesthetic consideratoins
elective procedures should be delayed until patient is optimized including infection control and secretion removal
vitk tx to absorb fat soluble vitamines
volatile agents: increased O2 concentration, relaxation of smooth airway muscles
awake extubation
adequate pain control
103
CF and anticholinergic medicaitons
avoid!
104
Primary ciliary dyskinesia
congenital impairment of ciliary activity in respiratory tract epithelial cells and sperm cells.
- patients may have decreased fertility
- good chance that all organs are reversed..
105
kartageners syndrome
triad of chronic sinusitis, bronchiectasis, sinus iversus (seen in half of patients)
106
anesthetic considerations for primary ciliary dyskinesia
regional anesthesia preferred
preop focus on pulmonary infection and organ inversion
reverse position of ECG leads r/t dextracardia
left IJ for CVC cannulation versus R
right uterine displacement versus L
avoid nasal pharyngeal airways due to sinusitis risk
107
bronchiolitis obliterans definition
disease of small airways and alveoli in children from RSV
108
bronchiolitis obliterans in adults may result from
viral PNA
collagen vascular disease (RA)
silo fillers disease (inhalation of nitrogen dioxide)
graft v host disease following transplantation
109
BOOP or bronchiolitis obliterans organizing pneumonia definition and tx
shares features of ILD and bronchiolitis obliterans. tx usually ineffective, corticosteroids and bronchodilators will be used.
110
tracheal stenosis reason it occurs
following prolonged intubation or over inflation of endotracheal tube cuff.
ischemia of tracheal mucosa results in scarring, may not appear for several weeks after intubation
111
when does tracheal stenosis become symptomatic
when diameter decreases to <5mm
dyspnea prominent even at rest
must use accessory muscles in all phases of breathing
112
tracheal stenosis treatment
tracheal dilation, temporary measure. balloon or surgical dilators, layering of scarred tissue
tracheobronchial stent can be shorter or long term solution
tracheal resection with anastomosis best treatment
113
tracheal stenosis anesthetic considerations
translaryngeal intubation
volatile agents to ensure maximum inspired oxygen concentration
helium, if available, decreases density of gas mixture and improves flow through narrowing
